The invention relates to a condensation polymer having at least one dialkylamide endgroup connected through the polymer backbone to a unit derived from an alkylamide, the connection comprising at least one ester linkage.
According to a preferred embodiment, the polymer according to the invention contains at least two groups according to formula (I) 
in which 
H, a (C1-C20) alkylgroup or a (C6-C10) arylgroup;
B=a (C6-C24) aryldiradical or a (C2-C24) alkyldiradical;
R1, R2, R3, R4, R5 and R6 may, independently of one another, be chosen from the group of H, (C6-C10) arylgroups or (C1-C8) alkylgroups;
R7 and R8 may, independently of one another, be chosen from the group of optionally heteroatom substituted (C6-C10) arylgroups or optionally heteroatom substituted (C1-C28) alkylgroups and n=1-4. Preferably, n=1.
According to a further preferred embodiment, the polymer according to the invention is a polymer according to formula (II): 
in which: 
H, a (C1-C20) alkylgroup or a (C6-C10) arylgroup; 
B=a (C6-C24) aryldiradical or a (C2-C24) alkyldiradical; 
R1, R2, R3, R4, R5 and R6 may, independently of one another, be chosen from the group of H, (C6-C10) arylgroups, (C1-C8) alkylgroups or xe2x80x94CH2xe2x80x94OX2;
R7 and R8 may, independently of one another, be chosen from the group of optionally heteroatom substituted (C6-C10) arylgroups or optionally heteroatom substituted (C1-C28) alkylgroups.
Preferably, R1 and R2 are both equal to H.
According to a further preferred embodiment, the polymer according to the invention has a number of dialkylamide endgroups xe2x89xa73 and the polymer is represented by formula (III): 
in which 
B=a (C6-C24) aryldiradical or a (C2-C24) alkyldiradical; 
R3 and R6 are chosen from the group of H, (C6-C10) arylgroups and (C1-C8) alkylgroups;
R7 and R8 may, independently of one another, be chosen from the group of optionally heteroatom substituted (C6-C10) arylgroups or optionally heteroatom substituted (C1-C28) alkylgroups.
In all above embodiments, preferably, R3 and R6 are (C1-C4) alkyl groups, more preferably a methyl- or ethylgroup. In all above embodiments, preferably, R7 and R8 are optionally hetero-atom substituted (C1-C20) alkyl groups, more preferably, R7 and R8 are hetero-atom substituted C2-, C3- or C6-alkylgroups. R7 and R8 may be substituted with a group selected from the group of alcohol, ether, ester, cyanide, carbonate, urethane, urea, amide, imide, amine, imine, imidazole, oxime, sulfide, thiol, thiourea, sulfon, sulfoxide, sulfate, fosfate, fosfine, fosfinoxide, silane, silicone, silicate, fluoro, chloro, bromo or iodo groups. Suitable choices for R7 and R8 are di(m)ethylaminoethyl, di(m)ethylaminopropyl, di(m)ethylaminohexyl, tri(m)ethylsilylpropyl, tri(m)ethoxysilylpropyl, perfluoro-octyl, perfluoro-octyl-(m)ethyl, (m)ethoxy-ethyl, (m)ethoxy-2-propyl, maleimido-propyl, maleimidohexyl, octenylsuccinimido-hexyl, hexahydrophthalimidohexyl, 2-(benz)imidazole-ethyl, difenylfosfino-ethyl, furfuryl, cyanoethyl, or cyanopropyl groups. R7 and R8 can also be part of the same optionally substituted cyclic group, such as a morfoline, thiomorfoline, piperidine, pyrrolidine, oxazolidine, thiazolidine or piperazine group.
In all formulas in this application in which R-groups are present, the R groups may together or with neighbouring carbon atoms form part of a cycloalkyl group.
Depending on the starting monomers chosen, B, R1, R2, R3, R4, R5, R6, R7 and R8 in the molecule or mixture of molecules can be selected to be the same or different.
B is optionally substituted, preferably with a (C1-C26) alkyl group. Preferably, the alkylgroup is chosen from the group of methyl, octenyl, nonenyl, decenyl, undecenyl or dodecenyl. Suitable choices for B are (alkyl-)1,2-ethylene, where the alkyl is defined as above, (methyl-)1,2-ethylidene, 1,3-propylene, (methyl-)1,2-cyclohexyl, (methyl-)1,2-phenylene, 1,3-phenylene, 1,4-phenylene, 2,3-norbornyl, 2,3-norbornen-5-yl or (methyl-)1,2 cyclohex-4-enyl radical.
Preferably, the weight average molecular mass of the polymer according to the invention is between 600 g/mol and 50,000 g/mol, more preferably between 800 g/mol and 25,000 g/mol.
Preferably, the number average molecular mass is between 500 g/mol and 15,000 g/mol, more preferably between 700 g/mol and 4,000 g/mol.
Preferably, the average number of dialkylamide endgroups per molecule is between 2 and 250, more preferably between 3 and 50.
The polymer according to the invention can be linear or branched. The linear polymer according to the invention generally comprises amide and ester units alternating along a chain as follows:
xe2x80x94Axe2x80x94Exe2x80x94Axe2x80x94Exe2x80x94Axe2x80x94Axe2x80x94Exe2x80x94Axe2x80x94Exe2x80x94Axe2x80x94Exe2x80x94Axe2x80x94
wherein a diamide (Axe2x80x94A) unit is coupled with alternating ester (E) and amide (A) units.
A branched polymer according to the invention generally comprises amide and the ester units alternating along the main and side chains as follows: 
wherein a diamide (Axe2x80x94A) is coupled with alternating ester (E) and amide (A) units.
Preferably, in the branched polymer according to the invention a (xcex2)-hydroxyalkylamide group is present, which can be both present as a bis-(xcex2)-hydroxyalkylamide endgroup, such as 
or as a pendant side chain group, such as 
Preferably, the molar amount of amide units in the chain is higher than the molar amount of ester units.